- Routine Inspections.
- Planning Surveys
- Surveys of known defects.
- Classification surveys.
- Annual surveys
- Intermediate Surveys
- Special surveys
- Condition Surveys
- CAP Surveys
- Life extension surveys, etc.
Fatigue cracking of steel structures:-
- Fatigue cracking occurs at points such as hatch covers where stresses are locally high.
- Such cracking is the result of cumulative damage caused by cyclic loading of structure & invariable starts at welded joints.
- The fatigue life is the time required in service for the structure to experience enough stress cycles for a crack to occur. A bulker is so designed that with proper maintenance cracking should not occur until a fatigue life span of 20 years.
- Fatigue life span once used up cannot be regained except by complete replacement of welded joints.
- Therefore, it is very essential that the welded joints of an overstressed structure are replaced, before proceeding with life exterior surveys/ programmes.
- Fatigue cracking have been most frequently observed in the bracket toes at the connection of the main frames to the hopper and topside tanks and in the boundaries of the vertically corrugated transverse bulkheads with upper stools, lower stools and topside tanks.
Corrosion / Structural Deterioration:-
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